Coupling



Feb, 9, 1943. w. A. Mz-:LsoM

COUPLING Filed May 21, 1940 -INVENTDR Mum/MMM Y @MA/ffm ATTORN EY in thestrength of with increaseinthe A Patenied @Febo i943 @opname WaiterArthur, Melsom, Willesden Sanction London, England, assignor to 'Bowden(Engineers) Limited, London,

'company England, a British .application May 21, 11.949, iSerial No.336,367

In Great Britain Aprillii, ld@

"i-ci'aim. lomas-s4) t t' The present invention relates to improvements1n hosecouplings of that type in which the end of the hose'ds grippedbetween a thin walledvv insert` and a surrounding sleeve which isradially contracted ontothe hose so as to grip the hose in a compressedcondition between the insert and the sleeve andin which a vscrew-mit isrotatably' mountedonthe insert and engages with a mating screw onanotherpart of the coupling in order Ato draw the latter 1 and thelinsert intoend-on sealedrelation, and especially `to that type ofcoupling infV which' the insert and thevsleve are, for' facility ofmanufacture, made of separate parts lioined together. y v

The invention deals with such couplings for medium pressure hoses, ybywhich we mean pressures oi iromfdOO to `2,0010 lbs/sq. in., andv highpressure hoses, Vby whichv we mean pressures up to 153,000 to 20,000lbs./sq. in., such hoses being employed for the' conveyance of gases,liquids,

' semi-solids or viscous substances. In orderto obtain a strong couplingfor these v relatively high pressures I cansecure a strong joint betweenthe hose, the sleeve and the insert, which I shall term the primaryjoint, by using a' circumferentially continuous thick' sleeve, i. e., asleeve which at least for the main part is thicker than the insertwithin the hose and when such a sleeve isradially contracted the largeamount of metal available for contraction-producesa good grip of thehose'which in turn tends to hold thesleeve' and insert against relativedisplacement.`

In the ordinary way the outer end of the insert is provided with anenlargement and the nut has an internal shoulder and is slidden over theinsert from the tail en d of the latter, i. e., that end which intrudesinto the hose in the nished couor the thickened part=thereof iS radiallycon-y .obtainedland at the same -o'f the secondary joint of saidconnection.`

a weak link in this dimculty I employ a dinerent form of nutinsertconnection which enables the required depth of engagement between theseparts tobe time allows thestrength to be chosen independently 'Accordingto the presentv invention therefore l in my medium' orhighpressure hosecoupling I employ a one piece hollow insert comprising an externallyreduced portion which is inserted in the` bore of the'fhose andaseparate sleeve member havlnga cirumferentially continuous wall whichwholly or partially is thicker than the reduced portion lof the insertand this sleeve tracted around the hose in order' to compress the hoseonto such reduced portion of the insert to form a primary joint betweenthe three parts, and such sleeve is provided with an axial extensionwhich is jointed and axially locked in both directions to the enlargedportion of i the insert to form the secondary joint of any pling. Thisinvolves making vthe body of the insert, including .the part which is tobe. jointed to the sleeve, oi less diameter than the aperture in thenut. As a result of any deepening of the engagement between the nut andthe insert to pro vide a greater shear resistance between these l partswhen the nut is drawing together the insert and the 'companion part witha pressure suited to the higher pressures for which the coupling isintended can only be obtained at 'the ex.- the thickness of the body ofthe insert and consequently .the strength of the and the insert which Ishall herein' term`.t he secondary joint,"whereas such jointcommenshear. resistance betweenthenutand theinsert d in the strength ofthe primaryfiolnt desirable so as not to have `ture with an annularsuitable strength and in lorder that the nut may be operatively mountedon the insert without regard in the dimensions of the latter at theregion of the secondary joint.rthe nut insert connection is made byproviding thewall of the .nut apergroove which surrounds an annulargroove in; the enlarged projecting portion of the insert, lthe twogrooves forming a passage to which access is had through the wall of thenut and means such as a wire or rod curved to a ring form ora series of.balls is introduced into said passage. The wire or balls allows the nutto rotate aboutthe insert and takes the thrust when the insert and itscompanion part are beingv sealed end-to-end bythe this kind between anut and a .companion part of a coupling has been V-previously proposed,but

not in combination with primary and Vsecondary joints or for the samepurpose, as hereinabove setforth. Various forms of couplings accordingto the present invention are illustrated by way of example in theaccompanying drawing, in which:

Figs. l and 2 are side elevation and end elethe coupling. In order toobviate vation respectively, each being half in section,

o f one form of coupling; Figs. 3 and (l are similar views of anotherand preferred form of cou- I pling; Fig. 3 showing the'screw couplingcom- Fig. 'I is a side elevation, partly inA section of anothermodication.

Referring to Figs. 1 and 2, the coupling nut I may be drilled or formedat what is normally its cap end 2 with an aperture 2 large enough topass clear over the joint end of the insert 4, this hole beingpreferably made slightly smaller-than the internal diameter of thethreaded portion of the nut so as to leave a. slight shoulderv 5.

An internal annular groove 6 is turned or provided in the wall of thishole. and an annular groove 1 of similar cross-section is formed in theexternal periphery of the insert 4, and these grooves register so as toform a ring-shape passage of rectangular crosssection.

For leading into this passage from the outside of the nut there isformed or drilled in the wall of the nut a rtransverse slot or hole 8. lI

When the nut has been assembled in place on the insert by being passedover the grooved connection joint end of the insert and havingregistered the grooves to form the passage, a". wire 9 of suitablesection to match the crosssection of the passage is then insertedtangentially into the nut and caused to ex to the arc of the passage,being subsequently dressed oi when the whole or substantially the wholeof the pasasge has been lled by it.

\ The passage may be of other cross section. In A fact a circularcross-section, as shown in Figs. 3 and 4 is preferred. In this case itis convenient to form registering semi-circular grooves I0, Il in theinsert and the inner wall of the nut respectively. In this form analternative and preferred entry to the passage is provided in the formof a hole I2 formed in the wall of the nut as 'a tangential continuationof the passage. In the latter case the wire may ll not only the passagebut also the tangential hole leading to' it Figs. and 6, in place ofwire, the passage may be-lled with balls 'I3 loaded through a hole I4whichn'aybe radially directed for enabling the hole morereadily to besubsequently closed 'by plug I5 to prevent ther escape of the balls.

With this form. as'in the `forms, shown in Figs. 1 to 4,-. the vcouplingnut may be used to break a pipe!connection,sincelthe balls' or'the wirewill thrust againsteither'side of the 'passage wall.

The thrust ,face or faces (forming. part of lthe wall vof the passage)of the joint end'of the insert may be either iiat orfmay be, machinedwith a radius to suit the proiileof the inserted wire. or balls ifdesired. l

The external contourof the nut may. be of plain hexagonalshape inaccordance'with the standards universally' adopted, orthe .nutf` may beexternally shaped by turning o the hexagons locally to reduce weightv orfor clearance purposes Any suitable materialsuch as brass, gunmetal,aluminium, aluminiumY bronz, dralumin and steel may be employed Vtoconstruct the nuts Yand. inserted locking wire.

Inonel form of couplingnut for use on aircraft pipe installations it isessential to drill a hole or holes transversely through the corner' ofthe hexagon lto accommodate a lock wire. f This oper--A when the wirehas been dressed o. The wire is inserted, according to the hand to whichthe nut is screwed, in such "a direction that the action -of tighteningthe nut tends to draw more-wire in the insert may be of suiiicient widthto permit this action (see 1a, Fig. 15), or alternatively the groove maybe replaced by a recess, as shown by 1b in Fig. 7. VThe effector this isto provider a lateral opening inthe passage which permits of themovement of the nut. along the insert in one direction. but doesmotprevent rthe wall of the passage from stopping movement of the' nut inthe other direction.

The :tit allowance of the nut and connection 4joint end of the insertand the size ofthe grooves are so chosen for preference thatapproximately half th e passage is formed in each part.

When the .wire lies one-half Ain the nut and l the other half in theinsert and the clearance ation is always relatively costly toaccomplish, and although it can be) done on the nut, thi subject of thepresent invention, it is preferred, in one form thereof, to machine thecap end of the nut on its-external faceto the form of an annular ring 30projecting away from the thread inan axial direction.

This ring Acan be arranged to provide ample diametral clearanceinternally between itself and the mating part of the nut, and lockwireholes 3| can readily be drilled into it in a radial direction toaccommodate lock .wire.

The present invention enables an improvement to be effected in thoseexible hose couplings of the kind in which a. contracted ferrule orsleeve of material I5, (Fig. 3) suited. to contractionl such asbrass,duralumin, low carbon steel, or

. phosphor bronze, clamps the Ihose onto the insert portion I6.

The fact that the nut is secured to its jointing part by a locking wireor equivalent enables the wall of the -jointing part to be increased inthickness where it is engaged by thesleeve or for the depth of theengagement between the nfutand the insert to be increased Withoutreducing the thickness of the remaining part of the insert.

In this way `it becomes possible to strengthen such couplings and incases wherethe insert is desired toA be screwed into the sleevesufficient metal is available to allow the insert to be screw threadedbehind a. shoulder and yet leave suiiicient strength at the root of thethread to resist the internal working pressure in the hose and theradial contracting pressure clamping the hose on' the insert.

As the nut can be attached to the insert after the latter has beencoupled to a hose all the op erations incidental to making the couplingbe without hindrance by the presence of the nut.

'As hereinbefore stated we prefer to use a locking wire 9 ofcircular'cross-section. If av radial shoulder on the nut bears againstthe radial face which is formed immediately behind an externallyspherical or conical sealing .end of the insert there is a liability forthe' outer part tween the insert and. the hose can be sectes broghtfintosealing relation end to end. with a companion fitting. a .separate metalsleeve `l member lhaving a circumferentially continuous wall which isradiallycontracted around the hose to grip the hose rmly between itseifand the in- 'sert and seal the inner wall of the hosewith the insert,said sleeve extending beyond the end of the hose so as'toycircumferentially engage the of such radial face to wear away and forthe in-` ner edge of the internal flange on the nutpto take the thrust.when this takes place th aange is liable to be bent back. The circularwirey and one tubular reinforcing layer, a olie-piece hollow metalinsert having an externally reduced por-"f tion inserted in the bere ofsaid hose and an enlarged portion beyond the end of the hose terminatingin an outer end portion adapted. to be said enlarged portion of theinsert, cooperative means interlocking said sleeve and insert togetherbeyond the end of the hose against rela- "tive axial 'movement 'ineither direction, a nut slidable overlthesaidtting engaging end portionofthe insert extending beyond the endof` said: sleeve ,-andlsaidaxialvinterlock, the inner wall oithe nu't andthe one-piece "insert where theintegral outre portionl thereof projects be-y yond said axialA-'terlocls(with the sleeve each an ainnuligu' groove; said grooves'register# ing to form .a'ring haped passage and ineens in-V troducedinto and' around the' f'said passageA to transmit the eiidthrust'ofthe'nut to the onepice insert wheny lthe insert and its Tcompanion ttingare being sealed end ,to end byl screwing saidnut to th'e toiwhich thevcoupling comj ponent is to beliltte'd.'l l

' j v WALTER AR'I'HUR MELSOM.

